Mycoremediation

Plastics become a common problem in waste management due to the fact that it takes hundreds or thousands of years to disintegrate into the environment. A step for bioremediation for plastics is using saprophytic fungi like the genus Pleurotus. The study explores the possibility that fungi of the said genus have the possibility to degrade the content of polyethylene. In this study, the researchers implanted the polyethylene films as a substrate in growth mediums with different soil and spawn content so the fungi will propagate on top of the plastic while degrading it. Observation was done within four weeks. Results show that the yield of the mushrooms is lower than cultivated mushrooms but the segment of the films have their densities depleted in four weeks’ time via electronic single pan balance test. This paper concludes that using mushrooms as plastic decomposers will be effective in degrading rubbish with the purpose of crumbling without problems and a few suggestions for the degradation of plastics using fungi. The importance of the present study is the potential use of mushrooms as a natural
decomposer for polyethylene plastics-in particular. Applications of these results can be proposed if the mushrooms are used to degrade the many plastics in landfills within a short period of time.

Keywords: Biodegradation, Pleurotus ostreatus, Mycoremediation, LDPE, HDPE

Soils and ecosystems worldwide are losing in fungal diversity, this is affecting their ability to respond to environmental changes and point perturbations. Also, pollution is rising and agricultural land is receding, creating a need to both manage our resources better and to regenerate the already “lost” land. Here, I am exploring how fungi and their mycelial
networks can assist us in this quest of co-habiting with the land to increase the quality of our lives. Fungi have multiple tools that can be of use here; a) fungal hyphae that colonize wide surfaces quickly and interconnect everything, occupy sensitive niches and strengthen the ecosystem. b) A whole army of enzymes that can degrade a wide range
of chemical contaminants and accelerate the re-cycling of  lignocellulosic material. c) Cellular structures capable of hunting and killing plant-pathogenic nematodes. d) The ability to adsorb and digest pathogens from running water thanks to their thick mycelial mats… Techniques such as mycoremediation can be used to decontaminate soils, mycofiltration can help us manage our waste waters locally and more efficiently, plantfungal interactions can help us strengthen our crops against pests, drought and saline stresses while increasing our yields. Certain fungal species of particular interest here are looked into more detail. Finally, a model is presented that combines all the different strategies presented in a small-scale homestead with animals, crops and mushroom production.

Textile industry is the most avid user for dyes. Rapidly growing interest in developing more synthetic commercial dyes from its native to endeavour human needs contributed to aesthetic problems to the environment and public health. Increasing concerns about colours in the effluents lead to worldwide efforts to develop more effective colour removal processes. However, the physical and chemical treatment methods of the discharge effluents are not economically feasible even if some of them are inefficient nowadays. Furthermore, liberating the hazardous product from secondary pollution from these methods acquires valid waste management system. Without proper discharge, azo dyes and associated chemicals may induce mutagenesis leading to toxicity in aquatic plants and animals. Utilization of mycoremediation of dyes as green chemistry technology has yet become a promising approach due to its clear picture of cost, eco-friendly and environmentally benign process as an alternative green solution to replace or supplement for current and future environmental issues. The bioremediation using fungi was reported to be more tolerant than bacteria and more efficient for decolorization as well as degradation of toxic chemicals. However, white-rot fungi are well known for their outstanding ability in bioremediation process. Their ability to produce highly non-specific extracellular enzymes allows them to degrade a wide array of pollutants resembling dyes and its derivatives. White-rot fungi secrete one or more of the three principle ligninolytic enzymes: lignin peroxidase (LiP, E.C. 1.11.1.14), Mn-dependent peroxidase (MnP, E.C. 1.11.1.13) and phenol oxidase (laccase) (Lac, E.C. 1.10.3.2) and other peroxidases. The present review discusses comprehensively the science and technology of biodegradation and fungal bioremediation of synthetic dyes.

A wide number of fungal species have shown incredible abilities to degrade a growing list of persistent and toxic industrial waste products and chemical contaminants to less toxic form or non-toxic form. Mycelium reduces toxins by different enzymatic mechanism to restore the natural flora and fauna. White rot fungi has successfully been utilized in degradation of environmental pollutant like polyaromatic compounds, pesticides etc. The present review gives a insights on degradation aspects of heavy metals, PAH especially using different fungal species. White rot fungi has potential to degrade contaminants using wide range of enzymes. Mycoremediation is promising alternative to replace or supplement present treatment processes.

Mycoremediation is an on-site remediation strategy, which employs fungi to degrade or sequester contaminants from the environment. The present work focused on the bioremedi-ation of soils contaminated with zinc by the use of a native mycorrhizal fungi (AM) called Funneliformis geosporum (Nicol. & Gerd.) Walker & Schü ßler. Experiments were performed using Triticum aestivum L. cv. Gemmeza-10 at different concentrations of Zn (50, 100, 200 mg kg-1) and inoculated with or without F. geosporum. The results showed that the dry weight of mycorrhizal wheat increased at Zn stressed plants as compared to the non-Zn-stressed control plants. The concentrations of Zn also had an inhibitory effect on the yield of dry root and shoot of non-mycorrhizal wheat. The photosynthetic pigment fractions were significantly affected by Zn treatments and mycorrhizal inoculation, where in all treatments, the content of the photosynthetic pigment fractions decreased as the Zn concentration increased in the soil. However, the level of minerals of shoots, roots, and grains was greatly influenced by Zn-treatment and by inoculation with F. geosporum. Treatment with Zn in the soil increased Cu and Zn concentrations in the root, shoot and grains, however, other minerals (P, S, K, Ca and Fe) concentration was decreased. Inoculation of wheat with AM fungi significantly reduced the accumulation of Zn and depressed its translocation in shoots and grains of wheat. In conclusion, inoculation with a native F. geosporum-improves yields of wheat under higher levels of Zn and is possible to be applied for the improvement of zinc contaminated soil.

Toxic chemicals are mostly released into the air, water, and soil due to anthropogenic activities or natural processes. These chemicals can be classified as organic or inorganic pollutants that can cause serious environmental contamination and render an environment inhabitable. Human activities help to proliferate chemical discharge (directly or indirectly) such as solvents, pesticides, and fossil fuels into the environment. Different approaches have been described as a means of environmental restoration such as the physical, chemical, and biological methods; however, transfer of contaminants from the point of source to an uncontaminated site limits this process. With the advent of biotechnology, a clear approach towards the use of microorganisms or plants for environmental restoration have been proposed and tested. Bioremediation is a very broad area of biotechnology that focuses on using phytoremediation and microorganisms as a strategy for environmental clean-up. For the most part, microorganisms play an important role in the transformation of organic and inorganic compounds in the environment. Some microorganisms use metals as a source of energy, and in return transforms it into a less toxic form. The time it takes to clean up a contaminated site depends on the concentration of the contaminants, the contaminated area, and among other physical conditions.
For an effective bioremediation, these factors have to be in place. Bioremediation can be applied at the site of contamination (in-situ) or through the removal of the contaminants to a different location (ex-situ) under the influence of certain conditions like temperature, pH, carbon source, and moisture. Thus, this review will focus on discussing the different approaches of bioremediation and phytoremediation using microorganisms and some plants respectively to safely maintain an eco-friendly environment. Both prokaryote and eukaryote that useful in environmental bioremediation are discussed in this review. They include but not limited to bacteria, yeast, algae, and fungi. Some plants that have exhibited similar characteristics are discussed as well. This review further addressed the different methods of detecting toxic metals in the environment. Understanding the mechanisms used by some microbes and plants to remediate environmental contaminants is still not clear and requires additional attention.

Mycoremediation is an on-site remediation strategy, which employs fungi to degrade or sequester contaminants from the environment. The present work focused on the bioremediation of soils contaminated with zinc by the use of a native mycorrhizal fungi (AM) called Funneliformis geosporum (Nicol. & Gerd.) Walker & Schüßler. Experiments were performed using Triticum aestivum L. cv. Gemmeza-10 at different concentrations of Zn (50, 100, 200 mg kg-1) and inoculated with or without F. geosporum. The results showed that the dry weight of mycorrhizal wheat increased at Zn stressed plants as compared to the non-Zn-stressed control plants. The concentrations of Zn also had an inhibitory effect on the yield of dry root and shoot of non-mycorrhizal wheat. The photosynthetic pigment fractions were significantly affected by Zn treatments and mycorrhizal inoculation, where in all treatments, the content of the photosynthetic pigment fractions decreased as the Zn concentration increased in the soil....

...Bioremediation is not a new concept kin the field of applied microbiology. Microorganisms have been used to remove organic matter and toxic chemicals from domestic and manufacturing waste effluents for many years. What is new, over the past few decades, is the emergence and expansion of bioremediation as an industry and its acceptance as an effective, economically viable alternative for cleaning soils, surface water and groundwater contaminated with a wide range of toxic, often recalcitrant, chemicals. Bioremediation is becoming the technology for the remediation of many contaminated environments, particularly sites contaminated with petroleum hydrocarbons...

Global consumption of petroleum and petroleum products draws the public’s attention to the fate of petroleum hydrocarbons in the environment, as they can permeate the soil environment in an uncontrollable manner. This study examined the physicochemical properties of soil heavily polluted with petroleum hydrocarbons using standards methods as described by the International Soil Reference and Information Center (ISRIC). Isolation and identification of fungi was carried out using enrichment technique, cultural morphology and microscopic examination. The isolates obtained were tested for ability to utilize BTEX using mineral salts medium (MSM) supplemented with 1% v/v BTEX as the sole carbon source for 7 days. The hydrocarbon-utilizing fungal (HUF) spore counts were determined by direct counting using Neubauer Haemocytometer. The petroleum contaminated soil has a characteristic gasoline odour and black in color. The texture of the soil was observed to be sandy, with slightly alkaline pH...

Mycoremediation is an on-site remediation strategy, which employs fungi to degrade or sequester contaminants from the environment. The present work focused on the bioremediation of soils contaminated with zinc by the use of a native mycorrhizal fungi (AM) called Funneliformis geosporum (Nicol. & Gerd.) Walker & Schüßler. Experiments were performed using Triticum aestivum L. cv. Gemmeza-10 at different concentrations of Zn (50, 100, 200 mg kg-1) and inoculated with or without F. geosporum. The results showed that the dry weight of mycorrhizal wheat increased at Zn stressed plants as compared to the non-Zn-stressed control plants. The concentrations of Zn also had an inhibitory effect on the yield of dry root and shoot of non-mycorrhizal wheat. The photosynthetic pigment fractions were significantly affected by Zn treatments and mycorrhizal inoculation, where in all treatments, the content of the photosynthetic pigment fractions decreased as the Zn concentration increased in the soil....

Nineteen filamentous fungi, isolated from estuarine sediments in Brazil, were screened for degradation of polycyclic aromatic hydrocarbons (PAH). The fungal isolates were incubated with pyrene. The cultures were extracted and metabolites in the extracts were detected by ...

... As such, they are good indicators of the degradation of sludge (Zule et al., 2007) and likely other materials. ... Various studies on VOAs and their correlation with degradation processes have been performed ([Kusel and Drake, 1999], [Strobel, 2001] and [Zule et al., 2007]). ...

Alpha-naphthol is a two-ring aromatic hydrocarbon with toxic and mutagenic properties. Bioremediation technology is considered to be an efficient, economical, and environmentally friendly approach to the remediation of the sites contaminated with polycyclic aromatic hydrocarbons. In this study, six fungal species of the Trichoderma genus were cultured in potato dextrose agar (PDA) media containing 10-200 mg/kg of α-naphthol for the adaptation of the fungal strains. The removal of α-naphthol was assessed 30 days after the growth of the adapted fungal colonies at various concentrations of α-naphthol (50, 100, and 150 mg/kg). According to the obtained results, all the fungi could grow in the culture media containing α-naphthol, removing α-naphthol from the media. The highest removal efficiency belonged to T. viridescens, while the lowest removal efficiency belonged to T. koningii. In addition, the growth ability of the fungi was determined based on the colony diameters, and the results indicated the highest and lowest colony diameters in case of T. koningii and T. viridescens, respectively. In other words, an inverse correlation was observed between the fungal growth rate and α-naphthol removal efficiency. On the other hand, the results of enzyme activity assay demonstrated that the activity of peroxidase and catalase increased with higher α-naphthol contamination. The highest enzyme activity was observed in T. viridescens, growing in the media containing 150 mg/kg of α-naphthol, which indicated a marked correlation between α-naphthol removal efficiency and enzyme activity. Therefore, it could be concluded that T. viridescens had the highest enzyme activity and α-naphthol removal efficiency.

Mycoremediation is an innovative biotechnology that uses living fungus for in situ and ex situ cleanup and management of contaminated sites. It is a cost effective process and the end products are nonhazardous. The process typically begins with field collection of fungi from a local area and continues with steps of culturing, screening, and preconditioning of native species to remediate specific contaminants. Industrial effluents entering into the surface waters are perhaps the most important sources of toxic contaminants in the environment. Textile is one of the largest industries which results in pollution contributed by untreated effluent discharge, which contains high concentrations of consumed metal based dyes, phenol, aromatic amines etc. The presence of metal based coloured dyes and foaming chemicals in textile waste water not only retards biological activity by reducing the light penetration but also causes metal toxicity to both aquatic and terrestrial life. There are vario...